Messaging client applications, Client MTMs and UI MTMs manipulate
entries through two classes, TMsvEntry and CMsvEntry. The entry currently being operated on is called
the context. A message client application can start by setting the
context to the root entry. By finding the children of this initial
entry, and then their children, it can find any entry.

Message type-independent operations are requested by message client
applications from and Client MTMs and UI MTMs through CMsvEntry or CMsvServerEntry. The
Message Server performs such operations itself or uses a Server MTM
to do them. For more information on how client requests are handled
by Message Server, see Handling Client Requests.